Process of making roads.



'ca-tes slowly break down giving clay,

JACOB S. ROBESON, OF AU SABLE FORKS, NEW YORK.

raocsss or MAKING" nous.

a-erzaese. 1510 Drawing.

To all-whom it may concern." I

Be it known that l, JACOB S. RoBEsoN, a citizen of the United States, resi ingat Au Sable Forks, in the county of Essex and State of New York; have \invented certain new and useful Improvements in cltrocesses of Making Roads, of which the following is a specification. i

This invention relates to processes of making roads; and itcomprises a process of preparing a highway prising clay, or clay yieldin'g materials, such as feldspathi'c and feldspathoid' minerals, such as feldspar, and rocks containing the same, suchas granites, gneisses, etc., and rocks containing the fcldspathoid minerals, leucite, nephelite, etc, such as the various basalts, traps, etc., as Well as such artificial silicates. as slags wherein a roadway of such material is treated preliminarily with caustic lime, either as quicklime or as slaked lime, to allow a certain chemical action upon such material to go forward and is thereafter treated with waste sulfite liquor or a preparation thereof; all as more fully hereinafter set forth and as. claimed.

Most )dirt roads are composed of or comprise clay, clay being one of the cominonest constituents of all ordinary soils, such as clays, loams, etc., and as is well known, the effect of alternate wetting and drying upon the clay of such roads is to make mud and dust. Clay is a very finely divided mineral material with little bonding power when simply dried down. Hard aggrega s or clods of. dried natural clay break down under vehicle wheels into the ultimate very fine constituent clayparticles which become dust. Macadam roads are frequently made of, various igneous aiid granitic rocks containingfeldspathic and feldspathoid minerals silicates containing alumina. and other bases, such as the alkalis. Under the in-,

fluence of weathering, these complex sili- (kaolin) and more or less colloid forms of silica and alkali silicates. The latter act as and furnish binding agents for the clay and unchanged mineral. These natural weathering and bonding actions are, however, very slow. But having a binding agent in the material of the road, these macadam roads for this reason, and also because they con- Specification of Letters Patent. Application filed March 6, 1912. Serial No. 682,014.

from materials comwhich ,are. comple K mama Oct. M, was.

tain a less amount of fine clay, do not dust quite so freely as dry dirt roads.

It is'an object of the present invention to convert the clay component of roads, Whether dirtroads or roads made of clay yielding materials, such ,as described, into a new form neither dusting nor yielding mud freely, and having a good binding power and to increase-and accelerate the breaking down or decomposition of clay-yielding minerals with production of clay and binder to form a dense, compact and sound road bed. Inthis connection it may be noted that most clays and soils or dirts usually contain proportions of feldspars and other clayyielding complex silicates.

a dirt road or a road macada'mized with silicate materials as previously described,

is first treated with a limited amount of finely divided. calcareous material as by a sprinkling or dusting of lime in some form. This limeis advantageously caustic and may be slaked o'r hydrated lime, or it may be quicklirne. It must be in a state of' fine subdivision to enable uniform application of the small-amount used. Quicklime is very soon converted into slaked lime in the road surface. Caustic lime applied to the road converts clay into a diflerent physical form and tends to destroy the natural binding power of the clay. This treatment in and by itself as applied to a dirt road would tendv to make the road dust even more freely thanbefore. But. the lime exercises an action" upon claywhich makes it better adapted for the next step in the operation. Andupon the granitic and igneous rocks of macadam roads and upon-the silicate particles in the clay, the lime exercises another specific action in that it attacks the surface of the minerals, producing uctsand accelerating the action which would naturally come with weathering. Some results of this attack of the lime upon these minerals are the production of clay, which is changed by the lime as 111st described 1n regard todirt roads,- and the production of new-forms of hydrated readily reactive silicates. For-this action of lime, either upon the clay or upon the rock, the presencep water is necessary. This may be supplied by. sprinkling or by rain. 'The lime application should be allowed to actupon the breaking down proderties to some extent; but for t; it at road for a day or two prior to the next treatment. A lapse of three or four days is advantageous.

The next step is to treat the road surface with Waste sulfite liquor or a preparation thereof. In the sulfite process of making paper pulp, Wood is heated under pressure with a solution of bisulfites; sometimes calcium bisulfite and sometimes bisulfites of lime and magnesia, dolomitic lime being frequently used for making the solution. About half'the wood goes into solution with the bisulfites and there are formed new and complex sulfur-containing organic compounds which are imchemical union with the bases of the sulfite liquor; lime or lime and magnesia. At least to some extent these new bodies appear to have the character of sulfonic acids; to be sulfonicacids derived from the lignone of the wood. For the sake of brevity the characteristic colloid organic solubles of the solution are generally called lignosulfonat'es of the bases employed; and this term will be hereinafter used. In the waste sulfite liquor as it comes from the digester these solubles evince valuable propmost purposes the raw or untreated liquoris not commercially useful. But by carefully neutralizing the raw liquor with lime and evaporating at low temperatures, a concentrated product (Patent 833,634) can be obtained in which the organic constituents are substantially notbroken up or decomposed but are in far more useful condition. There is some change in them in this operation, since the resulting liquid has more adhesive power per unit of dissolved matter than the original, liquor. ,[lhe concentrated more stable and retains this property even upon redilution. The contained solubles of sulfite liquor are of highly colloid nature and .this colloid nature seems to be enhanced in the described operation. But no fundamental chemical alteration of the organic complexes appears to have occurred.

Like many other organic characteristic colloids, the colloid bodies or lignosulfonates of the waste sulfite liquor and particularly of the concentrated product (Patent 833,634) have a specific action upon colloid mineral materials such-as are contained in clay, and

on the breaking down products of the-silicates. One effect of. either solution, and particularly of the concentrated solution, upon clay is to change its'character physically sothat upon drying down it makes hard, dense, coherent bodies of, comparatively, hlgh mechanical strength, not breaking down into dust forming particles as is the case with clay alone. In another and copending application 653,040, filed October 5, 1911, I have described and claimed the utilization of this effect of waste sulfite liquor products upon 'argillaceous materials,

spathoid minerals,

product is also scribed and claimed the treatment of roads containing clay with concentrated sulfite Waste liquor for the purpose of compacting and converting the road bed into hardened,

traflic-rcsisting masses. I have also found that this sulfite waste liquor material has a specific action upon feldspathic and feldspat-hoid minerals, increasing and accelerating their decomposition, converting the resultant kaolin into the bodies described and givin sundry additional advantageous binding e ects; possibly due to the reaction-with colloid alkali-containing. silicates so formed. This action is the case of roads containing limestone or the like in addition to thefeldspathic and feldspathoid minerals. I This matter I have described and claimed in plication 611,163, Feb. 27, 1911.

I have found that the action of waste sulfite liquor upon clay and clay-yielding materials, such as feldspathic and feldsame, is accelerated and improved by the stated preliminary taining the same with small amounts of lime in a finely divided state to produce a preliminary chemical change therein. In the present process therefore, I preliminarily apply a small amount of lime, advantageously caustic lime, uniformly over a preformed road bed to produce the stated preliminary action and render the materials more quickly susceptible to the action of the lignosulfonates; and then apply the lignosulfonate solution, either as the described concentrated product, which may be, and usually is, rediluted to a convenient strength for application, or in the form of some preparation of the sulfite liquor. The origiand rocks containing the particularly advantageous in my copendlng aln.

treatment of roads connal raw or crude sulfite liquor may be ap plied with advantage but is not so well adapted for the present purposes as the material of Patent 833,634, may be rediluted to a convenient strength for application. Another, form or modificatipn of the original sulfite liquorwhich is highly useful in the present connection is the residual liquor obtainedb fermenting Waste sulfite liquor and disti ling off the resulting alcohol. In this operation the soltible carbohydrates present in the original sulfite liquor are removed, leaving the which, if desired,

characteristic contained colloid sulfur containing bodies or lignosulfonates in the residual liquor in a purer state than in the raw liquor. This residual liquor is advanproduct containing the lignosulfonates in I tageously further concentrated, giving a v I moved. Other furic acid. Thisgives an as to its dilution which may be made by acidifying the concentrated vantageous to have the lignosulfonates of the solution in a more or lessv acid condition, or, at least'to have a solution having an acid reaction. A rapidly acting material product with suiiicieat sulfuric acid to liberate free lignosulfonic acid; This treatment produces calcium sulfate which may be reacid productsof good properties can bemade fate; or mixtures of bisulfate and free sulacid preparation containing in addition to free lignosulfonic acid some sodium lignosulfonate which is a useful body.

.The acidity of the'lignosulfonate solution may be that which exists in the sulfite liquor drawn from the digester; i. e. that due tothe presence of minimal amounts of free sulfurous acid, or bisulfites, and such raw digester liquor may be used in the present process. But owing to its stability and less colloid, or reactive, character, as well makes transporta tion difiicult, it is much better to submit the liquor preliminarily to-the treatment described in my Patent 833,634, and then subsequently render it acid. Rendering the liquor of acid reaction may be done by replacing the lime presentby a base giving acid-reacting salts, such as the sesquioxid bases, alumina, chromium oxid, and ferric oxid." The use of bases of this character for the present purpose with the sulfi f liquor has the additional advantage that they render it much more colloid in its character. ."Salts of'sesquioxids with colloid acids are always highly colloid. And I findthat the acid-reacting 1i gnosulfonates of iron, aluminum and chromium, are particularly suitable as road binders, 'in and of themselves. The use of such combinations of the organic matters of sulfite waste liquor with sesquioxid bases upon a road is cscribed and claimed in my copending application Serial No. 463,710, filed Nov. 20, 1908. In forming compositions of this character the concentrated waste sulfite liquor may be treated with a sulfate of the sesquioxid de-. sired 'to produce calcium sulfate, (which may be removed by filtration, if desired) and the soluble salt, or lignosulfonate, of the 'sesquioxid in question. For the present purposes the sulfate of calcium may be left in the mixture without much disadvantage, but it is better removed as by filtration. In thecase of the'iron compound, in lieu of making the ferric compound directly, ferrous sulfate may be employed to produce the ferrous compound of the lignosulfonic acids. In the road this will later absorb oxygen with a production of the sesquioxid and some incidental binding;

Having treated the roadway, whether of by using sodium bisulsulfite waste liquor are soluble clay or clay-y1eldingmineralsas described,

with caustic lime and leaving the lime to teact :upon the road materials for a suiiicient length of time, I may then treat the roadway with one of the described acid-reacting sulfite liquor preparations, as bysprinkling the road with a suitably diluted solution. I find with a clay road it is advantageous to treatthe road first with about one-half a pound of quicklime, or its equivalent in slaked lime per square yard, and to then sprinkle with waiter and allow the road to lie for, say, two days. I then treat with one of the'described waste sulfite preparations. A quantity corresponding to about thr'e'quarters of a gallon of the concentrated liquid of about 30 used for each square yard.

In lieu of the natural silicates described, I may use blast furnace slag. Roads containing blast furnace slag treated according to the present invention undergo changeswith lime and with sulfite liquor analogous to those described for the granitic and igne-' ous rocks. Y

to the nature of the actions of the sulfite waste liquor preparations described, I am not certain, but they are advantageous for road-making purposes and result in the production of a hard, concrete-like surface, very resistant to tra-fiic and dustingbut little. Apparently the organic matters of the sulfite waste liquor in changing the charac ter of the mineral profoundly changed. One result of this change of such organic matters is a conversion into forms, or combinations, which are resistant to water. The colloid matters of and there are hich will few, if any, chemical reagents w convert them into an insoluble form, except by such a physical action as by salting out. All the salts of lignosulfonic acid appear to be soluble. But on treating a roadway in the manner described the organic matters become insoluble and resistant to water. On a roadway made in the manner described becoming wet, the organic matters do not leach out, neither does the road become muddy. And by a prg with a little lime, the reaction of the-sulfite liquor in producing these results is much accelerated. Small applications of powdered limestone, marl, shells, domolite, gas lime, ets. may be used in lieu of caustic lime; but

their action upon clay and clay-yielding materials are themselves- Baum may be liminary treatment minerals is slow as compared with that of v caustic lime and they are not as well suited as the latter for the purposes of the present invention. The substantially neutral concentrated liquid of Patent 833,63-1 may be used but the stated acid-reacting prepara-' tions act more quickly and efliciently.

What I claim is 1. In the treatment of roadways comprising clay or clay-yielding materials, the process which comprises applying small amounts of finely subdivided calcareous matter to a preformed roadway of such material and thereafter treating with a sulfite waste liquor preparation.

2. In the treatment of roadways comprising clay or clay-yielding materials, the process which comprises applying caustic lime to such roadway and thereafter treating with a sulfite waste liquor preparation. 1

3. In the treatment of roadways comprising clay or clay-yielding materials, the process which comprises applying small amounts of. finely subdivided calcareous matter to a preformed roadway of thereafter treating with a sulfite waste liquor preparation having an acid reaction.

4. In the treatment of roadways comprising clay or clay-yielding materials, the process which comprises applying a calcareous material to such roadway, and thereafter treating with an acidified sulfite waste liquor preparation.

5. In the treatment of roadways comprising clay or clay-yielding materials,-the process-which comprises applying a calcareous material to such roadway, and thereafter such material and treating with an acidified sulfite waste liquor preparation containing some sodium lignosulfonate.

6. In the treatment of roadways comprisv ing clay or clay-yielding materials, the process which comprises applying caustic lime to such roadway, and thereafter treating with a sulfite waste liquor preparation having an acid reaction.

7. In the treatment of roadways comprising clay or clay-yielding materials, the proc ess which comprises applying caustic lime to such roadway, and thereafter treating with an acidified sulfite waste liquor preparation.

8. In the treatment of roadways comprising clay or, clay-yieldingmaterials, the process which comprises applying caustic lime to such roadway, and. thereafter treating with an acidified sulfite Waste liquor preparation containing some sodium lignosulfonat.

In testimony whereof, I ailix my signature in the presence of two subscribing witnesses.

V JACOB S. ROBESON. Witnessesi H. J. Lnoon'r'r, L. 0. Bonus. 

